As a background art, a) a technique of measuring a communication speed in a network, b) a technique of controlling a communication speed, and c) a technique of estimating throughput are described. Then, an effect of the technique of controlling the communication speed on the technique of estimating throughput is described.
a) A Technique of Measuring a Communication Speed in a Network
Information about an actual communication speed over a network to be accessed has a large influence on decision on a contract network operator and decision on an application to be used. However, information about the actual communication speed is not publicly available by the network operator. This is because a network service targeted for mass markets is a best effort service, in which only a maximum speed is determined within specifications and an actual communication speed depends on the number of users accommodated by each base station and/or each accommodation station, and thus the actual communication speed cannot be guaranteed.
However, a user needs information about an actual communication speed for selecting a network operator or a service to be used. For this reason, communication speeds on many services and media are measured and the measured result is released. One example is docomo (registered trademark) speed test that is an application for a smartphone (see Non-Patent Document 1). In this service, communication is performed between a server for speed measurement installed by a service provider and a user terminal, and an actually measured communication speed is displayed.
b) A Technique of Controlling a Communication Speed
Currently, a mobile network operator, in particular, sets an upper limit on a total data communication volume available to a user during a predetermined period of time due to an increase in a data communication volume used by applications. For example, each main MNO (mobile network operator) currently sets an upper limit on an available data communication volume depending on contract conditions and a communication speed is limited when a data communication volume exceeds the upper limit. For example, in a certain network service, a best effort service according to a specification of a base station is provided until a data communication volume exceeds the upper limit of 5 GB per month and when the data communication volume exceeds the upper limit, the communication speed is limited to a very low communication speed such as 128 kbps (see Non-Patent Document 2). In addition, most MVNOs (mobile virtual network operators), each of which is a virtual network operator using lines owned by an MNO, provide a network service in which a high speed data communication volume is low or zero (limitation on a low communication speed is imposed from the beginning) while a contract price is low, thereby differentiating themselves from the MNO (see Non-Patent Document 3).
c) A Technique of Estimating Throughput
In order to estimate a communication speed, an approach is provided for estimating the communication speed with reference to previous communication histories under the same environment. This approach make use of network constancy with respect to time and location. As examples of this approach, a media gathers measurement information about a communication speed and releases the measurement information by areas or by operators (see Non-Patent Document 4), and considerations are made for allocating resources in cloud computing or the like using information about the amount of traffic in network apparatuses or the like (see Non-Patent Document 5).
According to this estimation approach, conditions regarding time, a location, and so on are determined, a communication speed is measured for each condition over several times, and its average value is published. Since a bottleneck frequently arises in a base station in the case of a mobile network or in a connection point between an ISP (Internet Service Provider) and a carrier or between ISPs in the case of a fixed line, a communication speed is measured for each condition of the base station or the connection point.